Introduction

Data and Methods

Results

A. Visually compare annual salamander counts in old growth (OG) and clear cut (CC) sections of Mack Creek.

Figure 1: Annual count of Pacific gaint salamanders in CC or OG sections of Mack Creek (1993-2017). In both sections, the count of Pacific gaint salamanders generally increased from 1993 to 2011, dropped from 2011 to 2014, then increased again until 2017. In most years, salamanders in old growth sections have greater counts than those in clear cut sections.

B. Salamander counts by channel classification and sections of Mack Creek in 2017.

Table 1: Salamander count and proportions by channel classification (cascades, pool, and side-channel) in OG and CC in 2017. In CC section, 67.1% observations are from cascades (n = 247), 8.4% from pools (n = 31), and 24.5% from side channels (n = 90). In OG section, 62.8% observations are from cascades (n = 201), 14.1% from pools (n = 45), and 23.1% from side channels (n = 74).

Sections Cascades Pool Side-channel
CC 247 (67.1%) 31 (8.4%) 90 (24.5%)
OG 201 (62.8%) 45 (14.1%) 74 (23.1%)

C. Is there a significant difference in where in the channel Pacific giant salamanders are located between the two forest condition (OG and CC)?

There is no significant effect of forest conditions (GO/CC) on where in the channel salamanders are located (cascades/pool/side-channel) (\(\chi\)2(2) = 5.54, p = 0.06). Salamanders from old growth and clear cut sections in the forest have no different chances to be spotted in cascades (OG = 201 (62.8%), CC = 247 (67.1%)), pool (OG = 45 (14.1%), CC = 247 (67.1%)), and side-chanel (OG = 74 (23.1%), CC = 90 (24.5%)).

Summary

References